CN106602855A - Pre-charging device and method for support capacitor - Google Patents
Pre-charging device and method for support capacitor Download PDFInfo
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- CN106602855A CN106602855A CN201510683346.0A CN201510683346A CN106602855A CN 106602855 A CN106602855 A CN 106602855A CN 201510683346 A CN201510683346 A CN 201510683346A CN 106602855 A CN106602855 A CN 106602855A
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- resistance
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- support capacitor
- resistor
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Abstract
The invention discloses a pre-charging device and method for a support capacitor. The device comprises a main switch, a pre-charging switch, a first resistor, a second resistor, a first input end, a second input end, a first output end and a second output end; the first and second input ends are connected to two output ends of an external power supply respectively; the first and second output ends are connected to the two ends of the support capacitor respectively; the main switch is connected to the first input end and the first output end; the second input end is connected with the second output end; the first resistor and the second resistor are connected in series and then connected to the first output end and the second output end; and one end of the pre-charging switch is connected with the first input end, and the other end of the pre-charging switch is connected with a connecting point between the first and second resistors. Compared with the prior art, the device and method can be used to protect the support capacitor, prolong the service life of the support capacitor, reduce the voltage loss in the support voltage end, prevent a main contactor from electric impact when the main contact is started, protect the main protector, and prolong the service life of the main contactor.
Description
Technical field
The present invention relates to electric field, in particulars relate to a kind of pre-charging device and method for Support Capacitor.
Background technology
Support Capacitor is generally configured with the electric machine controller of prior art.Support Capacitor can store a part of electricity
Can, in real work, with charge and discharge attribute.Support Capacitor is for stablizing electric machine controller input voltage
There is extremely important effect.
The service life of Support Capacitor has important association with charging current.When having input power, power supply is to supporting electricity
Appearance is charged, and charging current is excessive, can reduce the service life of Support Capacitor.In order to increase Support Capacitor
Service life, it will usually construct pre-charge circuit to limit charging current.Pre-charge resistance is constructed most commonly
To limit charging current.
In addition, after electric machine controller breaks power supply, the electric energy being stored in Support Capacitor needs release, otherwise
There is potential safety hazard.Therefore generally it is also configured with carrying out forced electric discharge to Support Capacitor in pre-charge circuit putting
Resistance.
But in the electric machine controller main circuit structure of prior art, as pre-charge circuit designs unreasonable,
It is low that the pre-charge resistance partial pressure mutual with discharge resistance causes Support Capacitor terminal voltage to compare busbar voltage.At this
In the case of kind, main contactor is vulnerable to surge when closing, under inciting somebody to action so as to the service life that can cause main contactor
Drop is even damaged.
Therefore, in order to protect main contactor, a kind of new pre-charging device and method for Support Capacitor are needed.
The content of the invention
In order to protect main contactor, the invention provides a kind of pre-charging device for Support Capacitor, the dress
Put including master switch, precharge switch, first resistor, second resistance, be coupled with two of external power source it is defeated
The first input end gone out on end and the second input and be coupled with the Support Capacitor two ends it is first defeated
Go out end and the second outfan, wherein：
The master switch connects the first input end and first outfan；
Second input is connected with second outfan；
It is connected first outfan and described second defeated after the series connection of the first resistor and the second resistance
Go out end；
One end of the precharge switch is connected to the first input end, and the other end of the precharge switch connects
It is connected on the junction point between the first resistor and the second resistance.
In one embodiment, described device is configured to：
When described device quits work, the master switch and the precharge switch disconnect；
Close the precharge switch when described device starts first, be then turned off the precharge switch simultaneously same
When close the master switch.
In one embodiment, the master switch and the precharge switch are catalyst.
In one embodiment, resistance of the resistance of the second resistance more than the first resistor.
In one embodiment：
Described first resistor one end connects first outfan, and the other end connects the second resistance；
Described second resistance one end connects the first resistor, and the other end connects second outfan.
In one embodiment, the resistance of the second resistance is 20～100 kilohms, the resistance of the first resistor
It is worth for 1～10 kilohm.
The invention allows for a kind of electric machine control system, the system includes power conversion modules, Support Capacitor
And the pre-charging device as any one of claim 1-6, wherein：
Two inputs of the power conversion modules are connected respectively to the two ends of the Support Capacitor；
The two ends of the Support Capacitor are connected respectively to first outfan of the pre-charging device and institute
State the second outfan；
The first input end of the pre-charging device and second input are coupled with external power source
Two output on.
The invention allows for a kind of pre-charge method for Support Capacitor, constructs comprising master switch, precharge
The pre-charge circuit of switch, first resistor and second resistance so that when master switch disconnection, the preliminary filling
When electric switch is closed, the voltage at the Support Capacitor two ends is the voltage between two outfans of external power source, its
In：
The master switch connects one end of the Support Capacitor and an outfan of external power source, the support
The other end of electric capacity is directly connected with another outfan of the external power source；
The first resistor and the two ends for being connected the Support Capacitor after second resistance series connection；
One end of the precharge switch be connected to the external power source being connected with the master switch one is defeated
Go out on end, the other end of the precharge switch is connected to the company between the first resistor and the second resistance
On contact.
In one embodiment：
When the pre-charge circuit quits work, the master switch and the precharge switch remain open shape
State；
The precharge switch is closed first when the pre-charge circuit starts, and is then turned off the preliminary filling and is established by cable
Close and be closed at the master switch.
In one embodiment, the second resistance is connected to into the Support Capacitor and is directly connected to the external power source
One end；And the second resistance is set to into resistance of the resistance more than the first resistor.
Compared with prior art, device and method of the invention not only can protect Support Capacitor, extend and prop up
The service life of support electric capacity；And the loss of Support Capacitor terminal voltage can be reduced, it is to avoid main contactor is subject to when opening
Surge, so as to protect main contactor, extends the service life of main contactor.
The further feature or advantage of the present invention will be illustrated in the following description.Also, the part of the present invention is special
Levy or advantage will be become apparent by description, or be appreciated that by implementing the present invention.The present invention
Purpose and certain advantages can by specifically noted step in description, claims and accompanying drawing come
Realize or obtain.
Description of the drawings
Accompanying drawing is used for providing a further understanding of the present invention, and constitutes a part for description, with the present invention
Embodiment be provided commonly for explain the present invention, be not construed as limiting the invention.In the accompanying drawings：
Fig. 1 is the structure diagram of electric machine control system in prior art；
Fig. 2 is the structure diagram of electric machine control system according to an embodiment of the invention.
Specific embodiment
Describe embodiments of the present invention below with reference to drawings and Examples in detail, whereby enforcement of the invention
Personnel can fully understand how application technology means solving technical problem, and reach technique effect to the present invention
Realize process and realize that process is embodied as the present invention according to above-mentioned.If it should be noted that do not constitute conflict,
Each feature in each embodiment and each embodiment in the present invention can be combined with each other, the technology for being formed
Scheme is within protection scope of the present invention.
Support Capacitor is generally configured with order to stablize input voltage in the electric machine controller of prior art.Such as Fig. 1
It is shown, 100 for electric machine controller power control module, its output is connected to motor 102.100 base of module
Construct in insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT), its input leads to
Cross master switch K1 1(master flip-flop) is connected to external power source.Support Capacitor C1It is connected to power control module 100
Two inputs between (between two outfans of external power source), when equipment runs, Support Capacitor C1
By the discharge and recharge of itself come the input voltage of firm power control module 100.
Under usual condition, Support Capacitor C upon power-up of the system1Can be charged until fully loaded by Light Condition, now be propped up
Support electric capacity C1It is interior to produce larger charging current.Charging current is excessive, can reduce Support Capacitor C1Use
Life-span.In order to increase the service life of Support Capacitor, as shown in figure 1, preliminary filling is configured with electric machine controller
Circuit 101 is limiting charging current.Precharge switch (pre-charge contactor) is configured with charging circuit 101
K2 1And limit the pre-charge resistance R of charging current2 1。
Specifically, precharge switch K2 1With pre-charge resistance R2 1With master switch K after series connection1 1And it is connected in outside
On one outfan of power supply, whole system (Support Capacitor C is controlled1) power on/off.System is worked as substantially
During operation, master switch K is maintained first1 1Disconnect, connect precharge switch K2 1For Support Capacitor C1Precharge.
In pre-charge process, due to pre-charge resistance R2 1Limit electric current so that Support Capacitor C1Charging current
Will not be excessive, so as to protect Support Capacitor C1。
And then disconnect precharge switch K2 1And it is also turned on master switch K1 1So that system enters normal operation shape
State, carries out power conversion, motor work by power control module 100 (IGBT).Just enter in system
Support Capacitor C during normal running status1Charging is basically completed, therefore there is no longer excessive charging current.
When system is out of service, master switch K1 1Disconnect, due to Support Capacitor C1In be still stored with electric charge.
In order to eliminate safe hidden trouble, the electric energy being stored in Support Capacitor needs release.Therefore as shown in figure 1, preliminary filling
Discharge resistance R is also configured with circuit 1011 1.Discharge resistance R1 1With Support Capacitor C1Parallel connection, when master opens
Close K1 1During disconnection, discharge resistance R1 1With Support Capacitor C1Composition discharge loop, discharge resistance R1 1To supporting
Electric capacity C1Forced electric discharge.
But the design of the pre-charge circuit of above-mentioned prior art brings a problem.Define UDC 1For front voltage
(output voltage of external power source), UC 1For rear terminal voltage (Support Capacitor C1Both end voltage).In precharge
Stage, due to master switch K1 1Disconnect, electric current is through precharge switch K2 1With pre-charge resistance R2 1To support electricity
Hold C1Precharge.Line resistance is not considered, (actually line resistance is relative to R2 1And R1 1It is very little)
In the case of, master switch K1 1Before closure, UDC 1And UC 1Relation be shown below：
From formula (1), UC 1U to be comparedDC 1It is little.In a practical situation, due to R1 1And R2 1Parameter
Arrange, UC 1Only UDC 190%-95%.This will make master switch K1 1Surge, master switch are subject to during closure
K1 1Service life will decline and be even damaged.
In order to protect the master switch present invention to propose a kind of pre-charging device for Support Capacitor.As shown in Fig. 2
Device 201 includes two inputs (211 and 212) and two outfans (213 and 214).In device
Resistance R is configured with 2012 2, resistance R1 2, master switch K1 2And precharge switch K2 2。
Two inputs (211 and 212) of device 201 are coupled with two outfans of external power source,
Two outfans (213 and 214) of device 201 are coupled with Support Capacitor C2Two ends；Master switch K1 2
Connection input 211 and outfan 213；Input 212 is joined directly together with outfan 214；Resistance R1 2With
Resistance R2 2Connect between outfan 213 and outfan 214 after series connection；Precharge switch K2 2One end connect
It is connected to input 211, precharge switch K2 2The other end be connected to resistance R1 2With resistance R2 2Between connection
Point on.
When system stalls, device 201 also quits work, now master switch K1 2And precharge switch
K2 2Remain off.When system stalls, device 201 starts.Precharge switch K is closed first2 2,
Electric current passes through precharge switch K2 2Jing resistance R2 2After be output as Support Capacitor C2Precharge.It is then turned off preliminary filling
Electric switch K2 2And it is closed at master switch K1 2.So that device 201 enters normal operating condition, by external power source
Output directly export.
In device 201, U is definedDC 2For the voltage (external electrical between two inputs (211 and 212)
Output voltage/the front voltage in source), UC 2Electricity is supported (for the voltage between two outfans (213 and 214)
Hold C1Both end voltage/rear terminal voltage).In pre-charging stage, due to master switch K1 2Disconnect, now equivalent to
Support Capacitor C2With resistance R2 2With resistance R after series connection1 2It is in parallel to access circuit.Do not considering line resistance (line
Road resistance is relative to R2 2And R1 2It is very little) in the case of, master switch K1 2Before closure, UDC 2And UC 2Pass
System is shown below：
UC 2=UDC 2 (2)
I.e. in pre-charging stage Support Capacitor C2The voltage at two ends is consistent with the output voltage of external power source.This
Sample, when pre-charging stage terminates, device enters normal operating conditions (precharge switch K2 2Disconnect, master switch
K1 2Closure) when, master switch K1 2Surge is will be protected from just.
When system is stopped by working condition, device 201 also quits work, and now goes up master switch K1 2By closing
State goes off state (precharge switch K2 2Remain off).Resistance R1 2, resistance R2 2With support
Electric capacity C2Composition discharge loop.Support Capacitor C2On electric charge flow through resistance R1 2With resistance R2 2, resistance R1 2
With resistance R2 2To Support Capacitor C2Forced electric discharge.As, in discharge process, discharge loop is by resistance R1 2、
Resistance R2 2Two resistance compositions, can share thermal losses during Support Capacitor release electric energy.Compared to prior art
In the single discharge resistance of employing design, the service life of discharge resistance greatly increases.
In the embodiment shown in Figure 2, realize that the resistance for limiting pre-charge electricity is resistance R in pre-charging stage2 2
(equivalent to R2 2For pre-charge resistance), and the resistance for implementing electric discharge in discharge regime is resistance R1 2With resistance
R2 2.Therefore mainly implement the resistance of electric discharge (thermal losses during main support capacitor releases electric energy) in discharge regime
For resistance R1 2(equivalent to R1 2For discharge resistance).For loss and the consideration of electric current, set in the present embodiment
Put R1 2Resistance be more than R2 2Resistance.
Further, pre-charge resistance R is set2 2For several thousand ohms (K Ω) (1～10 kilohm).Due to
For Support Capacitor C2The forced electric discharge time have certain restriction, in Support Capacitor C2The situation that parameter is fixed
Under, discharge resistance is bigger, and discharge time is longer, usual discharge resistance R1 2It is set to tens of kilohms (K Ω)
(20～100 kilohms).It is noted herein that, the set point of above-mentioned resistance is the present embodiment
In a reference quantity.The resistance actual resistance of the device of the present invention is not limited to above range.In actual configuration
Need the actual resistance of resistance is specifically arranged according to the practical situation of system during circuit.
To sum up, compared with prior art, the method according to the invention not only can protect Support Capacitor, extend and prop up
The service life of support electric capacity；And the loss of Support Capacitor terminal voltage can be reduced, it is to avoid main contactor is subject to when opening
Surge, protects main contactor, extends the service life of main contactor.Further, side of the invention
Method shares electric discharge heat effect using double resistance, substantially increases the life-span of discharge resistance.
Based on device proposed by the present invention, the invention allows for a kind of electric machine control system.As shown in Fig. 2
System includes power conversion modules 200, Support Capacitor C2And pre-charging device 201.Power conversion modules 200
Output be connected to motor 202, the input of power conversion modules 200 is connected respectively to Support Capacitor C2Two
End；Support Capacitor C2Two ends be connected respectively to two outfans (213 and 214) of pre-charging device 201；
Two inputs of pre-charging device 201 are coupled with two outputs of external power source.
The invention allows for a kind of pre-charge method for Support Capacitor.It is real in the method according to the invention one
Apply in example, construct first as shown in Figure 2 comprising master switch K1 2, precharge switch K2 2, resistance R1 2And
Resistance R2 2Pre-charge circuit 201, wherein：
Master switch K1 2Connection Support Capacitor C2One end (213) and external power source an outfan (211),
Support Capacitor C2The other end (214) be directly connected with another outfan (212) of external power source；
Resistance R1 2With resistance R2 2Connect Support Capacitor C after series connection2Two ends；
Precharge switch K2 2One end be connected to and master switch K1 2On one outfan of connected external power source,
Precharge switch K2 2The other end be connected to resistance R1 2With resistance R2 2Between junction point on；
So allow for as master switch K1 2Disconnection, precharge switch K2 2Support Capacitor C during closure2The electricity at two ends
Voltage between pressure and two outfans of external power source is consistent.
The master switch K when pre-charge circuit (pre-charging device) 201 quits work1 2And precharge switch K2 2
Remain off；Precharge switch K is closed first when pre-charge circuit 201 starts2 2, it is then turned off pre-
Charge switch K2 2And it is closed at master switch K1 2。
Further, the resistance R that another outfan (212) of order and external power source is joined directly together1 2Resistance it is big
In resistance R2 2Resistance.
Compared with prior art, the method according to the invention not only can protect Support Capacitor, extend Support Capacitor
Service life；And the loss of Support Capacitor terminal voltage can be reduced, it is to avoid surge is subject to when main contactor is opened,
Protection main contactor, extends the service life of main contactor.Further, the method according to the invention is using double
Resistance shares electric discharge heat effect, substantially increases the life-span of discharge resistance.
While it is disclosed that embodiment as above, but described content only to facilitate understand the present invention
And the embodiment for adopting, it is not limited to the present invention.Method of the present invention can also have other various realities
Apply example.Without departing from the spirit of the present invention, those of ordinary skill in the art work as and can be made according to the present invention
Go out various corresponding changes or deformation, but these corresponding changes or deformation should all belong to the claim of the present invention
Protection domain.
Claims (10)
1. a kind of pre-charging device for Support Capacitor, it is characterised in that described device include master switch,
Precharge switch, first resistor, second resistance, be coupled with two outfans of external power source it is first defeated
Enter end and the second input and be coupled with the first outfan and second output at the two ends of the Support Capacitor
End, wherein：
The master switch connects the first input end and first outfan；
Second input is connected with second outfan；
It is connected first outfan and described second defeated after the series connection of the first resistor and the second resistance
Go out end；
One end of the precharge switch is connected to the first input end, and the other end of the precharge switch connects
It is connected on the junction point between the first resistor and the second resistance.
2. device according to claim 1, it is characterised in that described device is configured to：
When described device quits work, the master switch and the precharge switch disconnect；
Close the precharge switch when described device starts first, be then turned off the precharge switch simultaneously same
When close the master switch.
3. device according to claim 2, it is characterised in that the master switch and the precharge
Switch as catalyst.
4. the device according to any one of claim 1-3, it is characterised in that the resistance of the second resistance
Resistance of the value more than the first resistor.
5. device according to claim 4, it is characterised in that：
Described first resistor one end connects first outfan, and the other end connects the second resistance；
Described second resistance one end connects the first resistor, and the other end connects second outfan.
6. device according to claim 5, it is characterised in that the resistance of the second resistance is 20～100
Kilohm, the resistance of the first resistor is 1～10 kilohm.
7. a kind of electric machine control system, it is characterised in that the system comprising power conversion modules, support electricity
Hold and the pre-charging device as any one of claim 1-6, wherein：
Two inputs of the power conversion modules are connected respectively to the two ends of the Support Capacitor；
The two ends of the Support Capacitor are connected respectively to first outfan of the pre-charging device and institute
State the second outfan；
The first input end of the pre-charging device and second input are coupled with external power source
Two output on.
8. a kind of pre-charge method for Support Capacitor, it is characterised in that construction includes master switch, preliminary filling
The pre-charge circuit of electric switch, first resistor and second resistance so that when the master switch disconnect, it is described pre-
When charge switch is closed, the voltage at the Support Capacitor two ends is the voltage between two outfans of external power source,
Wherein：
The master switch connects one end of the Support Capacitor and an outfan of external power source, the support
The other end of electric capacity is directly connected with another outfan of the external power source；
The first resistor and the two ends for being connected the Support Capacitor after second resistance series connection；
One end of the precharge switch be connected to the external power source being connected with the master switch one is defeated
Go out on end, the other end of the precharge switch is connected to the company between the first resistor and the second resistance
On contact.
9. method according to claim 8, it is characterised in that：
When the pre-charge circuit quits work, the master switch and the precharge switch remain open shape
State；
The precharge switch is closed first when the pre-charge circuit starts, and is then turned off the preliminary filling and is established by cable
Close and be closed at the master switch.
10. method according to claim 9, it is characterised in that the second resistance is connected to described
Support Capacitor is directly connected to one end of the external power source；And the second resistance is set to into resistance more than described
The resistance of first resistor.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510683346.0A CN106602855A (en) | 2015-10-20 | 2015-10-20 | Pre-charging device and method for support capacitor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510683346.0A CN106602855A (en) | 2015-10-20 | 2015-10-20 | Pre-charging device and method for support capacitor |
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| CN106602855A true CN106602855A (en) | 2017-04-26 |
Family
ID=58555272
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| CN201510683346.0A Pending CN106602855A (en) | 2015-10-20 | 2015-10-20 | Pre-charging device and method for support capacitor |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111251911A (en) * | 2018-11-30 | 2020-06-09 | 比亚迪股份有限公司 | Electric automobile, charger thereof and charger control method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203368012U (en) * | 2013-08-07 | 2013-12-25 | 湖南南车时代电动汽车股份有限公司 | DC contactor combined circuit for electric automobile |
| CN204425003U (en) * | 2015-03-24 | 2015-06-24 | 长城汽车股份有限公司 | A kind of pre-charge circuit and hybrid vehicle |
-
2015
- 2015-10-20 CN CN201510683346.0A patent/CN106602855A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203368012U (en) * | 2013-08-07 | 2013-12-25 | 湖南南车时代电动汽车股份有限公司 | DC contactor combined circuit for electric automobile |
| CN204425003U (en) * | 2015-03-24 | 2015-06-24 | 长城汽车股份有限公司 | A kind of pre-charge circuit and hybrid vehicle |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111251911A (en) * | 2018-11-30 | 2020-06-09 | 比亚迪股份有限公司 | Electric automobile, charger thereof and charger control method |
| CN111251911B (en) * | 2018-11-30 | 2021-12-07 | 比亚迪股份有限公司 | Electric automobile, charger thereof and charger control method |
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Application publication date: 20170426 |